Final Exam 2 (20%)

Question

A string p is a prefix of a string s if the leading characters of s are identical to p. For example, "abc" is a prefix of "abcde". Develop a function prefix that checks if a C string p is a prefix of another C string s.

p是s的前綴若s開頭的一段字串等於p。例如，"abc"是"abcde"的前綴。寫一個程式 判斷字串p是否字串s的前綴。

Example input 1:

abc
abcde

Example output 1:

abc is a prefix of abcde

 

Example input 2:

bc
abcde

Example output 2:

bc is not a prefix of abcde

 

Answer 1

Hidden content!
 ***    * ** *  *   
**       * * *** *    * **

int main()
{
***   * *  * char    *  * 
 ***   ** * int i,c=0;
** *       ** **    * ***     * *  *   * ** **** 
*  *      *   *   ** * **   *  ***** *  *  **** **
*         * * *     *** *** ** * *   *
** ** ** *** {
* ** *    *      * ***  * ***** *** **
*     * *      * *  *  ** *** {
***      * * *    ***   ** ** *****  **   *  *  *  * *  * **  * *  
 ***** *  *  *  * *   **    *          *** * *   ***  **  ** {
   * *                 ** *    ** c=0;
 * ** *** *  * *  *  * * *   *   * ***   ***  *  *      *  ***** }
  *** *  * *****  **             **   *     ** *  * else        * *** *   ***  ***** *
**             **         * **    *  * ** * * ** ***  * {
** *    * * * * * **    **  * *    ** ** *      ****  * *     ** * *     c++;
  * * ** * ** * * ** *  *  * * * *    * **    *  **  * *   * }
**  *   *  **  * *  ** **   * **   }
   *     ** 
  *  ** * ** *   if(c==0)
*  * *   * **    * ** **    *    * * ** *     * is not a prefix of *     *   *  * 
 ***      ***  else
****  ** *      * *** **  **   * *   ***  *  ** is a prefix of **  *** * ***
*  *  *  * ** *  }
  ****   *  ** return 0;
}

Comments

prog.c: In function 'main':
prog.c:8:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&a);
           ^
prog.c:9:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&b);
           ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

prog.c: In function 'main':
prog.c:10:6: warning: implicit declaration of function 'stlen' [-Wimplicit-function-declaration]
   if(stlen(b)>strlen(a))
      ^~~~~
/tmp/ccnE3ufV.o: In function `main':
prog.c:(.text+0x5b): undefined reference to `stlen'
collect2: error: ld returned 1 exit status

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Correct output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 2

Hidden content!
* ****** * **   ****   *
 *** *  ** ** ******  * ** 
int main()
{
 ******   *  *  ap;
 *     ******* *** * ** *  * **          * || ap=a)
* * *   *    * * *     ** ** *    ***  **  *  ** * is a prefix of abcde\n");
** ** *  * ** **    
  *   * ***** ****
* * *    *******     * ** ****  * * ***  ** is not a prefix of abcde");
  * *** *** *    *  ** ** * * *  *  *  **    **** *    ** ** ****   **  *     0;
 *  * ***    *** ***  ****     * ** **  *** *   **    *  **   * * ***  
  

Comments

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

Answer 3

Hidden content!
** * *   *   * *  * 
** ***   **** ** ** * *

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
     ***  ** * *   *******   *** i<pl; i++)
  **  *  * * ** *   **  * 
  ****    * *   * **  ** * ***  ** * *   * * *  (p[i]==s[i])
  ***** * *     **** * *  * *  *   *    ***  *  
 * **  ** * **** * *        **      **   ** *** ***  ***   ** *   * *  *  **   *  *    
   *   * *     *  ****   *  * * *  *   * *    *    ** *** *** **  * ***
* ** *  * *  ** *  * *  ** *** * **  *  *** ***  *   *  *** ** ** *  *    *** *******   **  **  *** *** **** *  *** * *  1;
*      *   ***         * * *** ** **     *   * ***  ** * **  *  *** *  *    ******  *****
 *** *  *    * *  ***  *   *        * ***        *   ***  *  
  *  *    * *** ****   * ****  **  **** *** ***  ** **** if(p[i]!=s[i])
* * *    *** ** * *** * *  *    *** ****** * *   ** *   **
 *  ** *   *   *   ****    *   **   * *     ** *  **  *  *    **   ***      * 0;
 ** ***  * **   * * * ** * *    *     *** ********   *    *
   ****** ***     * **    **   
}


int main()
{
  *  * * *  *  
***** **     ***
* * ** *** *   *** ",p);
   ** *     ***     ** 
***          *   * **

sl=strlen(s);
pl=strlen(p);


**  * *   **  && pl<sl)
{

** ******  *   *  * *  *** **** ***********   is a prefix of %s",p,s);
}else
{
printf("%s is not a prefix of %s",p,s);
}





}

Comments

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 4

Hidden content!
#include<stdio.h>
#include<string.h>
int main()
{
  *   * ** *  * * *** *  ****  ** a[99],b[99];
    int l,i;
 ******** **  *** ***** *******   ** * ** 
**********      *   *** * ** * **   * *  *   
******   *  ****  ***  * **  *  *  
**   * ** *     * *  ***    *  **    ** * 
    {
* ****   ***    *  **** **  ***    *     **  ****   ** *** 
    * ***   *** *** * ** **  ** * ** *** * **  *   *
 * * ****** * *  ****  **  * *    *  *  * * **  * * ** ***  *  ****     * **    *    *** * ****  *  a prefix of %s",a,b);
  *      *** * **   ** *  ** ** * ** * * *  ** **  * *** **   *    ** **   * ****  *** ** 
  **    **   * **    * ***  * ***  *   * * * ** * 
   *  **    **  * *** **  * * ****  *  * * *** *  * ** * * 
 *  *     ***  ** *** *  ****   *    ** * *   * *  *
  * *  ***   ** * ****  ** ***  * ** * * **  **  *  *** **  * * ***** * ***      *   * **  *  *    not a prefix of %s",a,b);
 * * *   ***** * ***  * *  * ***** * *  *  * *  ****       ****   * * ***** * * **  *
*  *   *****   ******   *   **** *  *** * *  **** **
    }


}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 5

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

int prefix(char a[100],char b[100]);


int prefix(char a[100],char b[100])
{
    **      **  ****   ***  * i;
*  *   * **** *   ** **** * count=0;
* *  **  * **** *       *  *  len;

* * *      * *    ***   ** *  *  * *

  ****  *****  * * *       *   *     *   ** *
*     * ********  * *   * ** 
      ****  **   ** * * * * ** ***  ****   ***     *  
 ** ***  ****       **** * **   ** *    ** * *  
      *  *** ** *** * ** * *  *      ***** *    ** *    *    ****   *  ***  * ** * *
 ***** *     *  *  ****  *        ****  ***  *  * * ***** 
*   * *  *  * *  * **  * ** *


*   *  ****    *     **** * *    * 
 * ** *  * * *   * *    * * 
  * *** *  *****     * * *   **  * ***  * *  **     ****    1;
*    *** *  ***  *** * **  *
 *   ** *   *  * *       *    *

   return 0;
}


int main()
{
** * ** * ** * **  *  * ******* a[100];
*** * ***  * **    **   **  *  b[100];


 * * **    *   *  * *   **  *   *      * * ** *** * *** 
* ***   * * *  *  *** ** **    ********* *** * **** *****   

  *   **  **  ****** * *** *  ****** ****  
* *   ** * *  *  ** * ****    * * 

**  * * ** **      ** * ***  ** * **   

 {
* ** * * *     ***  ****  *    * *  * **   ** **  ** *   ** ****  is a prefix of %s",a,b);
*   * ** ** * **  ***  **  *  ****
*  *****    **** * ******** * * *
** *      * *** ***  ** **
*       * * * ** *   ****  * ****** ***     ***** *  ****  ** ***    * **  ** is not a prefix of %s",a,b);
 *  *   *   *  * *  ** *  *


*  ** ** *    **  ***  * ** *** ** ** 0;
}

Comments

prog.c: In function 'main':
prog.c:45:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&a);
               ^
prog.c:45:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&a);
                    ^
prog.c:46:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&b);
               ^
prog.c:46:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&b);
                    ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 6

Hidden content!
 * *      * *  **  * **
*  **             *  

int  * 
{
* *  **    **  * * *   * *  **** *   *** no idea, I   * even do it in the ** * *   * *  *   
   * ***  **** * *   *   *** 0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 7

Hidden content!
#include  ** **     **
#include * * *   *****    **
#include   *** *  **  *

int pref(char[],char[]);

int main(){

  * **** *** ** *  * *  **  * p[10],s[10];
***   *  ** ***** *** ****    num;

  *  *    * ***     * ***  *** *
** ** ** *   * *   *  *   ** *
   ***  *           * *      * **     ** ** ***  * *  
*   *** * *  ****   *  * *** *   * **** * **  ****    

*    * **       * * * *      *    = pref(p,s);

    ** *  ****** * **     ***   ** 
* * *      * * ** * * **** * *   **  ** *** ** *   **  *   * *  *   is a prefix of %s",p,s);
 **  ** **  * ****** * * * ** **   
**  *  *** ******** * * **  * *  **  ** ** ***  * * *  * *     * is not a prefix of %s",p,s);


 return 0;
}

int pref(char p[30],char s[30]){
*  *  *   * *   *  ** * * *  i;

 * *   *  **    *      *  *  *  *    ****** 
 *   *   **  ****   ** *   ** *** * ** * *   * * * * ** *****  *  * * ** * * **  ***  *  **  * * * * *  *   **
 ***   * **** * * *    * *   * * ***  *        ********** *  *  **** *  ** *****      * **   **  * * ***   * is a prefix of %s",p,s);
 **** * ** * *    **   *** *  **** * *** *   * *** ***   *     
**   * * *  *   * ** ****  **     ** * ********   *  * *    *  **   **   *** * *** *  **  *      *    **  is not a prefix of %s",p,s);

***      *  ** * **  ***** * *

}

Comments

prog.c: In function 'main':
prog.c:12:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:13:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/tmp/cc0tBG5r.o: In function `main':
prog.c:(.text+0x1f): warning: the `gets' function is dangerous and should not be used.

---

prog.c: In function 'main':
prog.c:10:13: error: stray '#' in program
     int num;#include <stdio.h>
             ^
prog.c:10:14: error: 'include' undeclared (first use in this function)
     int num;#include <stdio.h>
              ^~~~~~~
prog.c:10:14: note: each undeclared identifier is reported only once for each function it appears in
prog.c:10:23: error: 'stdio' undeclared (first use in this function)
     int num;#include <stdio.h>
                       ^~~~~
prog.c:14:1: error: expected expression before 'int'
 int pref(char[],char[]);
 ^~~
prog.c: In function 'main':
prog.c:23:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:24:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^
prog.c: In function 'main':
prog.c:51:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:52:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~

---

prog.c: In function 'main':
prog.c:14:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:15:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^

Answer 8

Hidden content!
* *  **    ****    **
    *    *  **    ***  

int main()
{
*  * length1,  ** * c;
******  * a[100];
  * **   ***  b[100];
 ********* d[100];

 ** **  * * **    ***   * ******      
****   **   **   ** *    * * 

 ** *  **  * * *  

**  *    *   **** *  *

    **  * **   *** *
 ****   
  ****     **  *** ** * *   is a prefix of *   *** *   **
**    * 
*******   *   
 * * 
* *  **   * **** *  is not a prefix of *   *  * *   
 **   * 

}

Comments

prog.c: In function 'main':
prog.c:11:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&a);
          ^
prog.c:12:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&b);
          ^
prog.c:24:11: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
           ^
prog.c:24:33: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
                                 ^

Answer 9

Hidden content!
**** ******** *      
 ******* ** *  *  * ****

int main()
{
 *** * * *   * *  ** **   *** **** str;
 ** * *    *  **  *  ***  ***  i, p, s;

  *  ** **  *** *** *  *  ***** * *   ****** ****  * * &p, &s);

  * **  *  **     ***  ** ***  (i<=0; &p; i++);
*** * * *   *    * *  ** ** *  
**  ** ** ****  ** **   * *      ****  *** * * ***  &p);
 ** *    ** *** * ***  **   * *** **  **  ***     * 
 **** * ** *   ** *  *  *
 **  **  *  ** ** *  *

    * *  **   * ** *  ****** ** 0;
}

Comments

prog.c: In function 'main':
prog.c:12:7: error: expected '(' before '{' token
     if{}
       ^
prog.c:13:12: warning: too many arguments for format [-Wformat-extra-args]
     printf("abc", &p);
            ^~~~~
prog.c:14:13: warning: format '%d' expects a matching 'int *' argument [-Wformat=]
     scanf("%d");
             ^

Answer 10

Hidden content!
**   *  * ***   *
* **  * *     * * *    *
int main (){
char ** *****
char *    ** **
* * ***  *    *   * * ** *  ***
* *     *   *****  *  ****   ** 
**** ** ****** **   ** *  **    *
 *  ** ** *** * ******  *** ** **
*  *        *  * *   *
 **  ** *  ** * * is a prefix of  **   **  * * * ** *  * *
}
else{
*  *     * ** * is not a prefix of %s  *** **  * ** ** * * 
}
**** 0;
}

Comments

prog.c: In function 'main':
prog.c:7:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string1);
         ^
prog.c:9:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string2);
         ^